Ana Rodrigues of the Centre for Functional and Evolutionary Ecology in France and her colleagues found that Amazonian towns in the midst of a deforestation binge initially see higher life expectancies, literacy rates, and incomes. But once the local forest is gone, income from timber typically dries up, the researchers believe; many farms and cattle ranches are abandoned after a few years because the nutrient-poor soil rapidly becomes depleted.

“The current development strategy results in a lose-lose-lose situation,” Rodrigues says. It destroys the rain forest habitat, fails to alleviate poverty, and contributes to global warming by eliminating trees that would absorb and store carbon dioxide. “The challenge now is to create a development path that is win-win-win.” One possibility, Rodrigues suggests, could be to create a provision in the next international climate-change treaty requiring wealthy countries with high carbon emissions to pay Brazilians for the environmental benefits of keeping their forests standing.